Anthraquinone vat dyestuffs



Patented Aug. 15, 1944 AN'rri'itAeUiNoNE v'A'rf Fra cis irv e and ii nry Alfred Piggott, Blackley,

Manchester, England, assignors Industries Chemical Great Britain a No 443,650. In

3 Claims.

This invention relates to the manufacture and application of new anthraquinone vat dyes. 7

These dyes are lzl-di-(p-alkylsulphonylbenzoylamino) -anthraquinones and l-benzoylamino- 4-p-alkylsulphonylbenzoyl amino-anthraquinones in which the alkyl group or groups have not more than 4 carbon atoms and may be normal or iso.

It has already been proposed to obtain dyestuffs, which yield on cotton bright scarlet to red dyeings, by introducing into the 1- and 4-positions of the anthraquinone molecule two aroylamino groups, at least one being a m-alkylsulphonylbenzoylamino group.

We have now found that dyestuffs with similar excellent properties to those of the prior proposal, but with a superior colour value, are obtained by introducing into the 1- and i-positions of the anthraquinone molecule two aroylamino groups, at least one being a p-alkylsulphonyl-benzoylamino group in which the alkyl group has not more than 4 carbon atoms.

According to the present invention new anthraquinone vat dyestuffs are manufactured by introducing into the land ll-positions of the anthraquinone molecule two aroylamino groups, at least one being a p-alkylsulphonyl-benzoylamino group, in which the alkyl group has not more than 4 carbon atoms and may be normal or iso.

The dyestufis may be made by diacylating 1:4- diaminoanthraquinone with a p-alkylsulphonylbenzoyl halide or with a p-alkylsulphonylbenzamide in the present of hydrogen chloride, or by acylating 1-amino-4-benzoylaminoanthraquinone with a p-alkylsulphonylbenzoyl halide or with a p-alkylsulphonylbenzamide in the presence of hydrogen chloride. Alternatively, the diacyl er monoacyl compounds may be obtained by interacting lz-dihalogenoor l-halogenoibenzoylaminoanthraquinone with a p-alkylsulphonylbenzamide.

The vat dyestuffs of the present invention dye cotton in very bright red shades of good fastness properties, and they have an excellent colour value.

The following examples, by weight, illustrate but vention.

in which the parts are do not limit the in- Ewample 1 To a nitrobenzene solution containing pmethylsulphonylbenzoylchloride, and made by heating together 26 parts of p-methylsulphonylbenzoic acid, 280 parts of nitrobenzene, and

Drawing. Applicati Great iiYEs'rUFFs 6 Imperial- Limited, a.v corporation on Mainline,- sit Britain May 2 (c1. std-372) parts of thionyl chloride at C., with stirring under a reflux condenser until complete solution and then removing excess thionyl chloride by distilling it from the solution at C., there are added at 150 C. 16 parts of 1:4- diaminoanthraquinone. The mixture is stirred and heated at the boil for 1 hours. cooling, the separated material is filtered off and heated under boiling water in a current of steam until free from nitrobenzene. The resulting dyestuff dissolves in concentrated sulphuric aci with a red-brown colour and dyes cotton from a bluish-grey alkaline hydrosulphite vat in bright scarlet shades of very good all round iastness.

p-methylsulphonyl benzoic acid is prepared by oxidising p-methylmercaptobenzoic acid with hydrogen peroxide in glacial acetic acid. crystallises from water in colourless needles, M. P. 264-559 3,

Example 2 14 parts of Example 3 30 parts of p-iso-propylsulphonylbenzoic acid are converted to chloride and condensed with lz-diaminoanthraquinone as described in Example I. There is thus obtained a bright scarlet dyestuff with properties similar to those of the product of Example 1.

The corresponding product from p-iso-propylsulphonylbenzoic acid and l-amino-l-benzoylaminoanthraquinone, prepared by the method of Example 2, is very similar in shade and dyeing properties.

-propylsulphonylbenzoic acid, M. P. 193 p-tolyl-iso-propyl sulphone (obtained from sodium p-toluene sulphinate and iso-propyl bromide) with potassium permanganate in neutral solution in presence o'f magnesium sul Example 4 1 6 parts of p-n-butylsulphonylbenzamide, '7 parts of lz4-diaminoanthraquinone and 100 parts of nitrobenzene are stirred at 200-2l0 C. while a acid gas is bubbled scribed in Examp e 1.

p-n-butylsulphonylbenzamide, M. P. 173 C. is prepared by adding p-butylsulphonylbenzoyl chloride slowly to concentrated aqueous acid (obtained similarly from p-tolyl n-propyl sulphone), M. P. 198 0., using methods similar to those described above.

e claim:

1. l-amino 4(p-a1ky1su1ph0ny1benzoylamino)- not more than 4 carbon atoms.

3. 1-benzoylarnino-4 -p-alkylsulphonylbenzoy1- amino anthraquinones in which the alkyl group contains not more than 4 carbon atoms.

FRANCIS IRVING. HENRY ALFRED PIGGO'IT. 

